The compression property resets to NULL, instead of the old value if we
fail to set the new compression parameter.
btrfs prop get /btrfs compression
compression=lzo
btrfs prop set /btrfs compression zli
ERROR: failed to set compression for /btrfs: Invalid argument
btrfs prop get /btrfs compression
This is because the compression property ->validate() is successful for
'zli' as the strncmp() used the len passed from the userland.
Fix it by using the expected string length in strncmp().
Signed-off-by: Anand Jain <anand.j...@oracle.com>
---
fs/btrfs/props.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/fs/btrfs/props.c b/fs/btrfs/props.c
index ef6502a94712..7aa362c2fbcf 100644
--- a/fs/btrfs/props.c
+++ b/fs/btrfs/props.c
@@ -277,11 +277,11 @@ static int prop_compression_validate(struct inode *inode,
const char *value,
if (!value)
return 0;
- if (!strncmp("lzo", value, len))
+ if (!strncmp("lzo", value, 3))
return 0;
- else if (!strncmp("zlib", value, len))
+ else if (!strncmp("zlib", value, 4))
return 0;
- else if (!strncmp("zstd", value, len))
+ else if (!strncmp("zstd", value, 4))
return 0;
return -EINVAL;
--
1.8.3.1
